(Continuation of Q.10/17)
Additional Recommendations, where needed, will be developed to accommodate
advances in technology and additional requirements from users of the ASN.1
notation, its encoding rules, and additional requirements from users and
providers of registration authorities for international object identifiers.
ASN.1 has proved to be the notation-of-choice for many ITU-T standardization
groups, many of which continue to produce requests for additional functionality
in the ASN.1 Recommendations and for correction of residual ambiguities and lack
of clarity in the more recent additions and amendments to those Recommendations
Object identifiers (OIDs) have proved a very popular namespace based
primarily on a tree-structure of hierarchical registration authorities
identified by integer value. Its recent extension to International OIDs allowing
arcs to be identified by Unicode labels is also in demand for various
applications, and is likely to produce requirements for further development and
There is a continuing requirement to provide advice and assistance to other
study groups, external standards development organizations (SDOs) and countries
on both ASN.1 notational matters but increasingly on the management of the OID
namespace. It is expected that the need for help and advice will increase with
the introduction of international OIDs. There is therefore a need for an ITU-T
"ASN.1 & OID Project" with an appointed project leader to provide such advice
Recommendations under responsibility of this Question as of 1 December 2008:
X.660, X.662, X.665, X.666, X.667, X.668, X.669, X.670, X.671, X.680, X.681,
X.682, X.683, X.690, X.691, X.692, X.693, X.694, X.695, X.891, X.892 and X.893.
Study items to be considered include, but are not limited to:
- What enhancements are required to the Abstract Syntax Notation One
(ASN.1) and its associated encoding rules to meet the needs of future
- What additional encoding rule support is needed to provide for the
requirements of the many applications using ASN.1?
- What additional packed encoding rules (PER) encoding instructions are
needed to allow protocol specifiers to vary those encoding rules?
- Are there requirements for additional generic applications of ASN.1 in
addition to X.891, X.892 and X.893?
- What additional Recommendations are needed to provide linkage between
ASN.1 and other notations for schema definition, particularly (but not
exclusively) related to eXtensible Markup Language (XML) mark-up?
- What further work needs to be done to ensure that the semantic
underpinning of ASN.1 is sufficient to support the "ASN.1 tools" industry
with a well-defined and unambiguous specification of the ASN.1 notation for
all possible input specifications?
- What further developments are needed in OIDs to support the work of
network aspects of identification (NID) and identity management (IdM) in
other groups and to integrate the different naming schemes in use in the
- What specifications are needed to support the provision of resolvers
related to international OID tree?
- What additional registration authorities or their procedures are needed
to support the work of this and other Questions?
- What collaboration, beyond current agreements, is required with other
bodies producing de jure or de facto standards to ensure that ITU-T work on
ASN.1 and OIDs remains a leader in the area of provision of notations for
protocol definition and for unambiguous naming?
- What changes are needed to the ASN.1 notation to allow the further use
of ISO/IEC 10646 characters?
- What support is needed for ASN.1 to play a role in the sensing and
alerting of events caused by climate change?
Tasks include, but are not limited to:
- Further the work on support for the IETF “oid:” Internationalized
Resource Identifier (IRI) scheme and its registration with the Internet
Assigned Numbers Authority (IANA).
- Provide updated Recommendations for X.660-, X.670-, X.680- X.690- and
X.890-series throughout the study period in response to user needs,
producing new editions when appropriate.
- When there is a need to improve data transfer, assist other Questions in
all study groups in the provision of ASN.1 modules equivalent to XML schemas
defined in ITU-T Recommendations (existing or under development),
particularly in low bandwidth situations.
- Consider extending the ASN.1 notation to allow the further use of ISO/IEC
- Under the responsibility of the ASN.1 & OID Project Leader:
- Provide general advice to users of ASN.1 and OIDs;
- Promote the use of ASN.1 and international OIDs within other study groups
and external standards development organizations (SDOs);
- Help the TSB to provide and maintain a web-based database of ASN.1 modules
defined in ITU-T Recommendations;
- Help countries with the establishment and maintenance of a national
registration authorities for OIDs (including international OIDs).
Recommendations: H.200-series, H.323, T.120, X.400-series, X.500-series,
X.700-series, X.880-series, X.900-series, Z-series and many others
Questions: All ITU-T Questions related to the above Recommendations
Study groups: All study groups that use ASN.1 or OIDs, or that have
identification needs in relation to NID or IdM
Standardization bodies: ISO/IEC JTC 1/SC 6 and all ISO/IEC WGs that use ASN.1
or OIDs; OMG; IETF; W3C; OASIS